Float valve structure



March 28, 1933. H. R. M PHAIL FLOAT VALVE STRUCTURE Filed Feb. 17, 1930 Patented Mar. 28, 1933 UNITED STATES mom) noY MCIPHAIL, or DETROIT, MICHIGAN,

nssreivon'r'o nonen conronn'rrom OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN FLOAT VALVE STRUCTURE Application filed February 17, 1930. Serial No. 428,877.

' Q 1 It is an object of this invention toprovide an improved float valve mechanism for the evaporator headers of refrigeration apparatus, wherein the refrigerant valve is POSltlVGF ly opened by the float mechanism but is not m rigidly linked thereto being-resiliently seated to prevent the valve seat from being damaged by reason of pounding thereof due to float movement from vibration or shocks incident to handling, shipment, and external vibrations during use; Heretofore, with the float mechanism directly linked to the valve, for operation thereof'in both directions, jars affecting the float position or even boiling of the refrigerant in the float chamber caused destructive pounding of the valve against its seat and it has frequently been found necessary to ship a refrigerating apparatus partially disassembled and to set up the outfit and charge the same with refrigerant at the place of use. With the present invention the entire assembly and charging. can be performed at the factory giving opportunity for final tests and sealing before shipment and delivery to the user. v I I It is another object of this invention to provide a simplified and serviceable evaporator header structure that can be economically manufactured and serviced after installation. Other and further important obj ects of this invention will be apparent from the disclosures in the specification and the accompanying drawing.

This invention (in a preferred form) is illustrated in the drawing and hereinafter I 4 more fully described.

On the drawing Figure 1 is a fragmentary front view of the header of a flooded type evaporator element The evaporator float chamber comprises a cylindrical shell 10 having one end 11 integral therewith, a' series of depending tubes l'2 be- Ing connected thereto beneath the normal liquid level marked 13. The tubes 12en'velop theusual freezer compartment 14; and are in turn covered by outer members 15 which reduce the formation of frost on the tubes and thus maintain the efliciency of theevaporator.

A suction outlet tube 16 extends through a closure or head 17 sealingly secured in the open end of the shell 10, this tube extending into and down close to the bottom of-an open top float 18 the position of the open end, of i the tube 16 being such as to assure removal of. liquid refrigerant, which may slop into the open float. If only a slight amount of liquid collects in the float the reduced pressure adjaccnt the inlet to the suction tube assures the removal thereof. The open float removesthe liability of leakage in a sealed float and thus increases the reliability of the apparatus. The float is limited in its downward move ment by the pivot therefor and inits upward movement by a stop 19which prevents the float mechanism' from pounding the float valve against its seat as will hereinafter be broughtoutQ w i I V The head or closure 17 is bored out to pr ovide an aperture 20 having an inner shoulder 21, a valve body. 22 having a shoulder 23 seating against the aperture shoulder 21. The valve body is really in two pieces,an outer body pieces 24 having an outstanding flange 25 on its inner end which engages against the outer face of the shoulder 23. .A gasket 26 is positioned against the outer face of the flange 25 and a packing gland 27 is screwed into suitable threads in the aperture 20 to both seal and clamp the shoulder 23 :9 and flange 25 against the shoulder 211- The outer body part 24 is threaded to receivean elbow 28, containing a removable screen 29, and the elbow in turn carriesa coupling for the high pressure refrigerant supply tube 31.

The inner valve body 22 is centrally apertured for a removable valve seat member 32 on its outer face so that unscrewing thepacking. gland and removing the outer valve body 1 being provided for the passage of refrigerant when the valve stem is even slightly withdrawn from its seat. The downward outlet reduces eruptions and prevents spraying of the incoming high pressure liquid into the vapor space in the shell 10.

The valve body 22 has an inward extension or bracket forming a support for the pivot 36 about which the float is hinged, a forked member 37, secured tothe float, straddling an outstanding tongue 38 on the bracket to support the float against side thrusts as well as limit the downward movement thereof,

short of contact with the shell 10.

The inner portion of the valve stem 38 may be reduced in diameter to form a retaining shoulder for a washer 39 as shown although it is obvious that the washer can be otherwise located in the desired position on the valve stem. The reduced portion of the stem is enveloped by a sleeve 40 having a shoulder ll opposed to the washer 39, a spring 42 being mounted therebetween. This sleeve 40 is pinned at 43 in the member 37 so that a downwardmoveinent of the float pulls back the sleeve, and an upward move ment of the float pushes the sleeve to the right increasing the spring pressure in the seating direction of the valve stem.

The sleeve 40 is slidable on the valve stem 33 anda'pina l secured inthe sleeve engages in an elongated slot 45 in the valve stem. The

position of the pin relative to the slot in the valve stem is such that a downward move ment of the float will engage the pin against the left hand end of the slot to mechanically retract 'or open the valve. The slot a5 is made long enough so that an extreme upward v. movement of the float will not engage the pin against the right hand end of the slot so that the only closing force acting on the valve stem is the resilient pressure of the spring 42. The spring seating of the valve stem prevents the valve seat from being ruined by pounding due to sudden movements or oscillation of I the float mechanisms since the sealing pressure can be predetermined and limited by suitable construction of the spring 42.

It will thus be seen that I have provided an improved and simplified float valve structure that will be durable and free from pounding on the valve seat and will be easily and economically constructed and serviced.

'I am aware that many changes may be made and numerous details of construction 1. An evaporator header tank for refrig- I erating apparatus, comprising a float chamber closed at one end, a head sealingly engaging the other end thereo f,a shouldered float valve body projecting inwardly through a shouldered aperture in said head, the shoulders on the body and in the aperture serving to locate said valvebo'dy, a retaining member abutting against said valve body, an external packing gland yfor clamping said retainer member and valve body shoulder against the aperture shoulder, a valve seat aligned with a valve guide aperture in said valve body, a valve stem engaging in one position against said seat, resilient means urging said valve stem towards its seat,'means for positively retracting, said valve stem against the action ofs'aid resilient means, and float mechanism for actuating said last-mentioned means. f r

2. An evaporator headertank for refrigerating apparatus, comprising a float chamber closed at one end, a head sealingly engaging the other end thereof, a shouldered float i valve body projecting inwardly through a shouldered aperture in said head the shoulders on the body and in the aperture serving to locate said valve body, a retaining member abutting against said'valve body, an external packing gland for clamping said retainer member and valve body shoulder'against' the aperture shoulder, avalve seat aligned with a valve guide aperture in said valve body, a valve stem engaging in one position against said seat, resilient means urging said valve stem towards its seat, means for positively I retractingsaid valvestem against the action of said resilient means, said retracting means having a one direction connection with the valve stem to prevent pounding of the stem against its seat, and float mechanism'for actuating said last mentioned means.

3. An evaporator header tank for refrigerating apparatus, comprising a float chamber closed at one end, a headjsealing'ly engaging the other end thereof, a shouldered float valve body projecting inwardly through a shouldered aperture in said head, the shoulders on the body and in the aperture serving to locate said valve body, a retaining member abutting against said .valve body,"'an external packing gland for clamping said retainer member and valve body "shoulder against the aperture shoulder, a valve seat aligned with a valve guide aperture in said valve body, a valve stem engaging in one po sition against said seat, and float mechanism for actuating saidvalve stem. i

4. An evaporator header for refrigeration,

apparatus, comprising a float chamber closed at one end, a head closing the other end thereof, said head havin an opening therethrough, a shouldered vave body including a portion projectin into said chamber through the opening, a oat operatively associated with said valve body portion within said chamber, said valve body including a laterally extending portion engaging said head on an outwardly disposed surfacethereof for limiting the inward movement of said body, said head including a threaded portion, clamping means for said body, com rising a clamp element bearing against sai laterally extending portion of said body for retaining the body inposition, and means having threaded engagement with the threaded portion of said head and bearing against said clamp element for holding the clamp element in position.

5. An evaporator header for refrigeration apparatus comprising a float chamber having an opening therein, a shouldered valve body having a portion projecting within said chamber through said opening, and also having a laterally extended portion engaging an outwardly disposed surface of said chamber for limiting the inward movement of said body, a float operatively associated with said valve body within said chamber, clamping means bearing against said laterally extending portion of said body for retaining the latter in position upon said chamber surface,

and threaded means engaging a threaded portion of the opening in said chamber and bearing against said clamping means for holding the latter in position.

In testimony whereof I have hereunto subscribed my name at Detroit, Wayne county,

Michigan.

HAROLD ROY MGPHAIL. 

